CAPF AC 2022 Q19: Science & Technology – Biology
Phloem tissues are mostly responsible for transport of
- (a) water
- (b) oxygen
- (c) minerals
- (d) food
Answer: (d) food
Explanation
What phloem carries
How to think: plants have two transport tissues.
Xylem carries water up.
Phloem carries food.
| Tissue | Carries | Direction | Main cells |
|---|---|---|---|
| Xylem | Water and minerals | Upwards only, from roots | Tracheids, vessels |
| Phloem | Food (mainly sucrose), amino acids | Both ways, from leaves to all parts | Sieve tubes, companion cells |
The name of the process: movement of food in the phloem is called translocation.
It uses energy from ATP.
Answer: (d) food.
Why each option is right or wrong
- (a) Incorrect. Water is carried by the xylem.
- (b) Incorrect. Oxygen moves by diffusion through stomata and air spaces.
- (c) Incorrect. Minerals travel with water in the xylem.
- (d) CORRECT. Phloem transports food made in the leaves to all parts.
Key point
Xylem: water and minerals, upward, driven by transpiration pull. Phloem: food (translocation), both directions, needs ATP. Phloem parts: sieve tubes, companion cells, phloem parenchyma, phloem fibres.
Remember
Phloem = food; xylem = water.
Common mistakes
- Mixing up the two tissues and giving water to the phloem.
- Thinking minerals travel separately in the phloem instead of with water.
- Believing phloem carries food only downwards; it works in both directions.
Exam tip
Educated guess: remember the pair phloem = food by the shared sound of ph and f. Xylem then takes water.
Sources
- NCERT Class X Science — Life Processes (transportation in plants)
- NCERT Class IX Science — Tissues (complex permanent tissue)